IHM 0172

CTD stations on 20W line from 50N to 20N, following the old WOCE line A16N Physical measurements (CTDO and LADCP) and discrete samples for salt, oxygen, inorganic nutrients and alkalinity/inorganic carbon Underway ADCP, surface ocean measurements, surface meteorology measurements. Contribution to GO-SHIP sustained hydrography program. Partial repeat of a hydrographic line last occupied in 2003.

Timing and frequency of landslide and gravity flow geohazards along the eastern North Atlantic continental margin This research cruise was a contribution towards the NERC strategic science programme (Oceans 2025). The main scientific objective was to improve our understanding of landslide and gravity flow geohazards along the eastern North Atlantic margin, in particular by studying event timing and frequency in the recent geological record. Special attention was being paid to geohazards that may potentially impact UK communities and infrastructure. Shallow piston coring of turbidite successions in deep basins produces the best record of recent (<50 kyrs) gravity flow events on adjacent margins (e.g. Weaver et al., 2000), but the availability of pre-existing data from the study area was patchy. Consequently, a key aim of JC027 was to 'fill the gaps' and recover cores from basins, or sections of basins, where data are urgently required. A total of 60 piston and megacores was successfully recovered during the cruise, from a series of lower canyon and basin floor environments. Shallow geophysical data, including subbottom profiles and hull-mounted multibeam bathymetry, were collected quasi-continuously during the cruise to define local environment around core sites. In complex areas, such as seafloor scours, Autosub6000 was deployed to collect high-resolution EM2000 multibeam bathymetry.

Objectives: To quantify marine halocarbon emission variability and latitudinal variation, characterise in situ open ocean atmospheric reactive iodine latitudinal variability and characterise oxidative chemistry perturbation due to oceanic emission of halogens from the Mauritanian upwelling region. Rationale: Transecting from the UK through Biscay, south past the west coast of Africa, through the Mauritanian upwelling, to pass Cape Verde simultaneous to the intensive deployment at the UK SOLAS Observatory on Sao Vicente, the measurements made on Discovery cruise D319 are intended to provide a detailed latitudinal characterisation of marine atmospheric halogen chemistry. This will feed validation and constraint data to regional and global models in projects linked to RHaMBLe. In addition the cruise will address a number of key scientific questions required to determine the global importance of iodine chemistry and to further our understanding of the controls of halogen chemistry in the remote ocean: i) How heterogeneous are the direct halogen sources and on what scale is the heterogeneity - does the upwelling region produce more or less halogens than the 'background' region? ii) What are the relative contributions of I atoms to the remote MBL from I2 and organic iodine? iii) Is sufficient iodine released to the remote MBL to sustain aerosol nucleation or to significantly affect the ozone budget and free radical populations? Measurement Description: Measured species included a variety of halocarbons in both water column and atmosphere and atmospheric boundary layer measurements of I2, OIO and IO by Broadband Cavity Enhanced Absorption Spectroscopy (BBCEAS). A compact version of the FAGE system, developed for the FAAM BAe-146, was deployed to provide measurements of IO or OH / HO2, permitting direct assessment of RHS-induced changes in the oxidising environment through the upwelling region. A range of trace gas monitors was simultaneously deployed to measure O3 and NOx. Aerosol number and size distribution measurements from 3 nm to 20 micron diameter were also made by a range of mobility (SMPS) and optical instrumentation, (OPC and FSSP). Additional aerosol measurements were provided as part of the NERC-funded ACMME project (PI Allan). Measurements of pigments in the surface waters were made by HPLC. Prevailing meteorological conditions were used to direct the cruise in terms of geographical positioning and measurement interpretation, e.g. i) exploitation of any broad flow connection between Cape Verde and the ship to interpret measurements as process studies and ii) identification of in- and out-of-plume conditions to contrast chemistry influenced and uninfluenced by emissions from the upwelling region.

To estimate nitrogen (NH4+, NO2-, NO3-), phosphate and silicate fluxes in the Strait of Gibraltar, to quantify and characterise the fluxes of particulate organic carbon and nitrogen (POC/PON) and to estimate of picoplankton, nanoplankton and microplankton biomass distribution in the Strait of Gibraltar To describe the hydrological structure and the geochemical fields of the region of the Gulf of Cadiz, particularly at the levels influenced by the Mediterranean waters, in order to set a background for interpreting the dynamics of the Outflow

Our project aims at assessing the different biogeochemical processes controlling the nitrogen cycle in oligotrophic N.E. Atlantic waters. Our approach is based on the use of dual nitrate isotope measurements (natural abundance and enrichment experiments) to disentangle these various N processes in the marine environment, and in particular the process of diazotrophy by which atmospheric N2 is introduced into the oceanic fixed nitrogen reservoir. This input of "new" nitrogen should stand in balance with the denitrification process by which N is lost from the oceanic system. There are indications that the intensity as well as the geographical distribution of diazotrophic activity has been underestimated till date. Our observations, made the past few years, indicate that diazotrophic activity is present in the Azores Current region (DIAPICNA, EUROFLEET cruise; July 2011) and along a meridional section through the Atlantic Ocean (EUROPA cruise; European Universities & Research On board RV Polarstern in the Atlantic, Nov. 2012). During the EUROPA cruise maximal fixation rates were observed around 20°N, south of the Canary Islands, but diazotrophic activity was detected at all latitudes, even at 38°N , the northernmost station sampled during the EUROPA cruise. It is of interest to better document diazotrophic activity at latitudes of 38°N and northward. We propose to study the different biogeochemical processes acting on the marine N-cycle, including N2 fixation, along a N-S section through the Gulf of Biscay to Cape Finistere and further south in open ocean waters along the Iberian peninsula till about 36°30'N. On board we will measure primary production, N-nutrient uptake and N2 fixation in the euphotic layer, using 13C, 15N enriched incubation experiments. We also will sample the upper 1000m of water column for nutrient concentration and N-nutrient natural isotopic composition analyses. This investigation will be coupled with a newly started PhD project, financed by FNRS (Aspirant mandate) and in co-tutelle between ULB and VUB, aiming at studying the impact of the marine iron biogeochemistry on the phytoplankton and the diazotroph communities. During the campaign, we shall perform incubation experiments using in-situ oligotrophic surface waters to examine the influence of the addition of dissolved iron and that of natural desert dusts on the phytoplanktonic production and diazotrophic activity.The AUMS project is inspired by the success of similar systems deployed on various ships of opportunity in the framework of the European Union FerryBox project (www.ferrybox.org). The instrumentation will greatly enhance the continuous oceanographic measurements made by RV Belgica by taking advantage of the significant technological improvements since the design of the existing (salinity, temperature, fluorescence) systems. In particular, many new parameters can now be measured continuously including important ecosystem parameters such as nitrate, ammonia, silicate, dissolved oxygen and CO2, turbidity, alkalinity and phytoplankton pigments. In addition, the new equipment allows automatic acquisition and preservation of water samples, rendering RV Belgica operations significantly more efficient by reducing onboard human resources. Data will be available in near real-time via the public website of OD NATURE and following quality control, from the Belgian Marine Data Centre.Collection of GNSS data in the maritime environment for performance evaluation under different conditions.Aim of the project is to cultivate marine bacteria able to degrade hydrocarbons at both atmospheric and high pressure, in aerobic and anaerobic environments. Kill-Spill is an European funded FP7 project focusing on the development of highly efficient, economically and environmentally viable solutions for the clean-up of oil spills caused by maritime transport or offshore oil exploration and related processes. It provides new tools to promote novel (bio)technologies in oi